Back when I was writing my own custom JavaScript functions, I learned that there wasn't a single, simple way to change the individual style settings (like "font-weight:bold") for an HTML element that worked on every browser. My solution was to change the CSS classes assigned to the element instead: I wrote a library function that would allow me to add, remove, or replace any class assigned to an HTML element and simply created as many class definitions as I needed in order to accommodate the style changes. It was actually a pretty effective workaround because it let me effectively change multiple styles with one function call.

When I started using jQuery, I quickly learned about the "addClass" and "removeClass" core functions, which I could use instead of my library function:

...So I continued with my routine of changing styles by changing classes, even though sometimes I only needed to change or remove a single style setting. No harm, no foul.

But changing classes wouldn't work for the wacky little project I've been working on recently: I needed to be able to change several styles for an HTML element individually, and writing a class to handle every permutation of the possible style combinations was impractical.

So I went to the jQuery web site, hopeful that the brilliant folks at jQuery had something that could help me out.

And they did: the "css" core function allows you to read or set any individual style or styles: